Lu Zhong-Lin, Chu Wilson, Dosher Barbara Anne, Lee Sophia
Department of Psychology, University of Southern California, Los Angeles, CA 90089-1061, USA.
Vision Res. 2005 Sep;45(19):2500-10. doi: 10.1016/j.visres.2005.04.009.
We combined the external noise paradigm, the Perceptual Template Model approach, and transfer tests to investigate the mechanisms and eye-specificity of perceptual learning of Gabor orientation in visual periphery. Coupled with a fixation task, discriminating a 5 from an S in a rapid small character string at fixation, contrast thresholds were estimated for each of eight external noise levels at two performance criteria using 3/1 and 2/1 staircases. Perceptual learning in one eye was measured over 10 practice sessions, followed by five sessions of practice in the new eye to assess transfer. We found that monocular learning improved performance (reduced contrast thresholds) with virtually equal magnitude across a wide range of external noise levels with no significant change in central task performance. Based on measurements of learning effects at two performance criterion levels, we identified a mixture of stimulus enhancement and external noise exclusion as the mechanism of perceptual learning underlying the observed improvements. Perceptual learning in the trained eye generalized completely to the untrained eye. We related the transfer patterns to known physiology and psychophysics on orientation direction coding.
我们结合了外部噪声范式、感知模板模型方法和迁移测试，以研究视觉外周Gabor方向感知学习的机制和眼特异性。结合一个注视任务，即在注视点处快速的小字符串中区分5和S，使用3/1和2/1阶梯法在两个性能标准下针对八个外部噪声水平中的每一个估计对比度阈值。在10个练习阶段测量一只眼睛的感知学习，随后在新的眼睛中进行五个练习阶段以评估迁移。我们发现，单眼学习在广泛的外部噪声水平范围内几乎以相同的幅度提高了性能（降低了对比度阈值），而中心任务性能没有显著变化。基于在两个性能标准水平上对学习效果的测量，我们确定刺激增强和外部噪声排除的混合是观察到的改善背后的感知学习机制。训练眼的感知学习完全推广到未训练眼。我们将迁移模式与已知的关于方向编码的生理学和心理物理学联系起来。
